The location where a fan could hit the fuselage at dangerous speeds is probably well concealed no? As in, once spinning it's probably feasible that the fan hit

The location where a fan could hit the fuselage at dangerous speeds is probably well concealed no? As in, once spinning it's probably feasible that the fan hit the fuselage on the back, in the area right next to the fans, but unlikely that it hits on the front, near the cockpit, far from the fan. I wonder if it could be an effective strategy to re-enforce the parts of fuselage that could be hit instead of encasing the fans themselves.